MSD vs. Mallory electronic
 

Hello all.
I'm debating the ignition for my 517" bbc.
9.5 to 1 pump gas
Brodix plus 2 heads (fully worked)
Naturally aspirated

Thoughts:
MSD=might suddenly die
Does my boat need the multiple sparks down low to avoid loading up?
The Mallory marine electronic distributor looks like a nice piece.

In short, am I better off with a stand alone electronic ignition ( no box ) or do I really need a capacitive discharge ignition such as an MSD?

Opinions please.

Thanks, rob

[ATTACH=CONFIG]520841[/ATTACH]

I used the Mallory magnetic breakerless distributor in my 383ci with great success . Still looked like new inside the day I sold it . I think the MSD will rust just sitting in the box .

Just wanted to show you this picture of my marine MSD I just bought a year ago only used it for about 3 months in fresh water and this is what it looks like. I'm going to call them and see what they have to say about it.

I hear that the proof is in the picture.

You must have checked the " pre - rusted " button in the option box when ordering .

I run MSD no springs or any moving parts. Timing is locked out @ 34 degrees with no issues for 4 years now

Thanks for the replies.

That sure is an extreme case of corrosion. I had an MSD on my old boat for years and nothing like that.

I'm more concerned about the "box" and having the inevitable failure.

Is the mallory made here in the states?

Is there a good solid reason for a capacitive discharge ignition in a boat?

Am I going to load up plugs in "no wake" zones with a standard electronic breakerless ignition (no box)?

Thanks again, rob

When the idle starts fluctuating in my muscle car I know it's time to clean the rust and change the springs in my MSD distributor. It never see's water! WTF

ive run my 4x4s underwater... try using some silicone to seal up the dist...sheesh

Daytona sensors and a merc oe hall effect dist..the box is pricy but it wont break!!..http://www.daytona-sensors.com/products_ignition.html

I really appreciate all the responses but, can anyone outline the reason to use a capacitive discharge ignition on a marine application?

Trying to determine if I really need a "box" or if I can simplify it with only an electronic breaker less ignition.

Thanks, rob

if your running a big cam it really helps burn all the fuel so it dont load up..other then that its the cool factor ..lol

rob,you did not mention what cam you are useing but imo if the tuneup is right and it is not overly rich at idle you could use a merc t bolt 4 dist or any good quality stand alone dist.i recently learned of a way to stop the rust issues inside the msd,or any dist from a very wise man.after you get it all cleaned up spray the metal parts with crc sp400.NO MORE RUST.

Thanks mike. Not sure what bob will spec for a cam yet.
I have the flow numbers and compression nailed down but I need to ensure the dry headers I have will fit so I can let bob know if the exhaust will be wet or dry.

Thanks to all for responding.

So to sum it up, the multiple spark ignition is good for low rpm usage so as to not load up plugs.

I've certainly heard a lot of bad about MSD and I have had to replace my 6M after 10 years. I also had to pull my distributor and clean it up, also after 10 years. I used gun blue and treated all the steel components and then a light coat of WD40. That was 5 years ago and everything still looks like it did 5 years ago. Whether or not you need a CD box, depends on a lot of factors. I have a pretty lumpy cam, I'm carbureted and I like to cruise down the inland waterway which is at least an hour of idling. With my current MSD setup I can idle for an hour, get to the lake and stand on it and no signs of spark plug loading. I have also checked the plugs after a long river cruise and they look great. The advantage of the MSD is that it is marine approved so no Coast Guard or Insurance issues. I looked long and hard at the Mallory ignition when I did my rebuild but stuck with the MSD because the Mallory tech recommended against a marine application. I did add a vent tube to my distributor cap and will be connecting it to my air cleaner housing to help pull moisture out of the distributor. The advantage with the MSD is the availability of all types of custom advance bushings, I tried several different types before I settled on locking mine at 34 degrees. Also their HVC 2 coils rock for voltage spark duration and current. I'm just relating my experience, my boat starts as fast or faster than any of my state of the art EFI cars and trucks.

Malloy sells a stand alone, electronic breaker less, distributor that is us coastguard rated and carries a "marine" label.

Mallory marine is also infinitely adjustable as far as amount and timing of advance.

The rusting issue, like Mike Tkach said, can be solved by coating a new distributor internals, with CRC SP-400. I did mine a few years back, they still look great.

As for "NEEDING" a CD ignition, I say, no you dont "need" it. The multiple sparks at low rpm, isnt a "bonus" so to speak of. Its because it is NEEDED, with a CD style ignition. Most people think, ''Oh, multiple sparks at low rpm, must help for fouling plugs''. Thats really not why they have it. It is an area by design of that particular style ignition, that simply needs help, in that area. A conventional ignition, doesnt need those multiple sparks at low rpm. Its about the duration of the spark. CD ignitions have a short spark duration, where a conventional one will have a longer spark duration. At low engine speeds, the multiple spark, makes up for the loss of spark duration.

So, is there really any advantage to a "box" ignition if the notion that the multiple sparks down low don't actually help the plugs from fouling?
Is the idea that the msd improves idle quality and prevents plugs from loading up not true?

I'm not suggesting they don't work. I run cd ignitions and very happy with them. I know the 525sc, 600sc, 800sc ran merc ignitions, and unless someone messed with the carbs, plug fouling was not an issue. The thing I like is having the ability to change timing curves, which you really can't do with a merc ignition

MSD recommends to run a noise filter to keep the voltage spikes from taking out the box. I have had msd on my boat for 10 years no problems yet. As for the rust I put extra vents in the dist. cap it seemed to help some. I hope I did not jinx my self with this post!

If you are asking if you need to run a box, the answer is no, you will not run any faster, if may or may not clean up the idle..depends on carb/cam, timing...the only real gain would be a rev limiter if box has one and you feel you need one, you can buy one of the cheap HP HEI, and run fine, used several of them and the only real fail item(and I have never had one fail) is the module and you can keep a spare and change very easily...Rob

the msd box does give you more duration of spark,,7* to be exact so the spark stays their a little longer at idle then a regular distributor would..they usually cut out at 3500 rpms..the only reason i have one is because the temperature drop on the lakes and rivers i run and they are not constantly the same..it can vary up to 20* sometimes and i dont run a thermostat,,just a restrictor plate..i just got sick of constantly adjusting my carberator,,and hollys are cold harted *****s..

Reviving this thread.
Time to buy an ignition system.
Anyone have experience with the msd "ready to run" distributors? No box and retail at around 400 bones.
I'm seriously considering the mallory marine electronic distributor but it would need an "add on" rev limiter.

Anyone running the mallory marine unit?

Thanks, rob

If I had 400 to spend, I'd go with the Mallory pro billet dist, which is identical to msds pro billet but cheaper, and a crane ign box. That would be about same cost but better ignition imo. Or possibly the Mallory pro billet with the msd 6 programmable box for a very tunable timing curve

How would the DUI stack up to those?

Wow I thought mine was bad the first time I took it apart. I call MSD they said they know about the corrosion issue. But had no solution for it. There are vents in the bottom mine were plugged up. After the rebuild my builder suggested drilling the cap and did so thru one of the towers that excepted the screws for the wire hold down that I do not use.

Not to hijack the thread. Where do most people mount their box. Mine is on the transom. Do the engine mounted boxes cause the for mentioned failures heat and vibrations?

Msd boxes are junk plain and simple. Doesn't matter where you mount them. You can have a brand new box that doesn't work. Doesn't matter if it Auto or Marine they are junk.

I'm using a Jesel front mount distributor and Daytona box on my new build.

mallory version 154.99

http://www.jegs.com/i/Mallory/650/85551M/10002/-1

MSD version 249.99

http://www.jegs.com/i/MSD+Ignition/121/85551/10002/-1

[QUOTE=vintage chromoly;4247769]Reviving this thread.
Time to buy an ignition system.
Anyone have experience with the msd "ready to run" distributors? No box and retail at around 400 bones.
I'm seriously considering the mallory marine electronic distributor but it would need an "add on" rev limiter.
Anyone running the mallory marine unit?

We ran the Accel / Mallory dual sync for years without any problems. I beleive most of their distributors have copper where MSD uses steel that corrodes. Never had a problem with the MSD Digital 6 mounted behind the rear seat. My brother runs the Crane box never an issue there either. The Rev limiter helps alot if you brake a drive shaft and the RPMs go crazy high...

i have been running those msd dists for 3 years now in my cat so far so good !!!

2X Mallory Unilites!!! I ran MSD for awhile on the my boats, but never could seem to get them sorted out. Moved everything to Mallory Unilites and it's been "set and forget" ever since.
I also had the MSD Offroad 6 on my rockcrawler, and the boxes kept giving up. At one time, I had two (2) MSD boxes on it (switched) lost both within months. MSD said they knew about the problem, were good at replacing the boxes, but I gave up on them. Stuck a DUI in the rockcrawler----holy crow----that cleared the low end fuel load, throttle response was awesome---I got nothing to say but good things on DUI. Never ran in a boat (yet) but I am well pleased.

JMHO--MDS seems like there always some "issue" --something not quite right in some aspect of their operation. Like the corrosion in a Marine distributor? really? I would stick to Mallory or DUI.

Yes, I have been running a Mallory marine magnetic pickup. Not unilite since 1998 with no issues on a 509" 500 hp engine.

I bought a Mallory magnetic electronic distributor and a Daytona sensors cd- 1 marine ignition.
The only thing I'm asking of the distributor is to trigger the "box" and distribute the spark. The timing curve and rev limiter will be done by the cd-1 ignition module.

Did the sad box come with the ignition curve information for each setting? When Crane made a similar box the curve info for all common Mercruiser high performance engines was on the website, now I cannot find it. I am trying to compare the ignition curve of a HP 500 carb to the HP 500 bulldog (540cu in).
Sounds like you will have a good setup

The Daytona box comes with all the merc curves and you can do a custom curve with a laptop.

I recently had a MSD 6M fail preventing me from getting to Lake Havasu Desert Storm this year. I bought a Daytona Sensors CD-1 along with the coil and a 2 bar MAP sensor. My engine is a Donovan aluminum block 540 with a 14-71 blower at ~8lbs boost, 2x 1050 carbs, and a not too aggressive hydraulic roller cam. Before I had issues when dropping into gear engine wanted to die, but with idle stabilization I add 14 degrees when rpm drop below 750 and all is good, doesn't die. With the MAP sensor, I was able to create a 3D timing map and load it into the cd-1 so now when in boost the box pulls timing as required. After knowing how the engine ran before with the MSD billet distributor and 6M box compared to now with the cd-1 DS box, I'm sold. Borowski race engines in Illinois is where I got mine, ask for Ken and an OSO member price break, you won't be disappointed.

The fact that you are asking this question.......... Do MSD's really have a reputation for failing boxes??? LOL! You have already answered your own question!! Why would you by an MSD for a boat?? It's not like you can just pull over to the side of the road WHEN it dies!!! What if it dies when your caught in some really snotty weather in rough seas??

Don't forget their junk coils. Had to new msd coils in one season. First one was a long tow. Second one didn't get towed but had someone bring my trailor to a different ramp and pick me up. I will never buy anything MSD again.